1. Field of the Invention
This invention relates to a procedure for the qualitative determination of .alpha.-amylase in a sample, and more particularly to a diagnostic agent for the enzymatic determination of .alpha.-amylase. The qualitative measurement of .alpha.-amylase concentrations in a sample is useful in medical diagnostics.
2. Discussion of the Prior Art
The enzyme .alpha.-amylase is to be found in salivary and pancreatic juices. It is well known that this enzyme reacts with various carbohydrates, particularly starch, to form maltose, and that the enzyme maltase will react with maltose to form glucose. These two reactions form the basis for intestinal digestion. See, for example, Biochemistry by Cantarow and Schepartz, page 263.
It is also well known that the presence of glucose can be determined by various coupled reactions. This knowledge has led to several proposed methods for measuring amylase activity in conjunction with maltose by utilizing its ability to convert starch to glucose. See, for example, the article by H. W. Schiwara in Arztl Chab. 17:340-343 (1971) and the paper entitled Columetric Rate Determination of Serum Amylase Activity given at the National Symposium on Enzyme Chemistry in 1972.
Techniques involving starch, however, do not allow truly quantitative amylase determinations. The amylase reacts with each of the constituents of starch to produce different reaction products, and the kinetics are unpredictable. This is particularly troublesome in rate determinations where the measurements are made within a short span of time, during which the reaction kinetics are even less predictable. As a result of this, measurements made using starch as the substrate for .alpha.-amylase activity do not, and in fact cannot, give a true measure of .alpha.-amylase concentrations in the test sample.
Furthermore, the test proceedings of the prior art are not capable of differentiating between salivary .alpha.-amylase and pancreatic .alpha.-amylase.
It is an object of the present invention to provide a diagnostic agent for the determination of .alpha.-amylase which allows quantitative measurements to be made. It is a further object of this invention to provide a diagnostic agent which can be used in a rate determination process for the determination of amylase so that a rapid quantitative measurement of the amount of amylase present in a sample can be made.